Status Review of the Ringed Seal - Alaska Fisheries Science Center

265 Pages·2010·8.68 MB·English

NOAA Technical Memorandum NMFS-AFSC-212

Status Review of the Ringed Seal
(Phoca hispida)
by
B. P. Kelly, J. L. Bengtson, P. L. Boveng, M. F. Cameron, S. P. Dahle,
J. K. Jansen, E. A. Logerwell, J. E. Overland, C. L. Sabine, G. T. Waring,
and J. M. Wilder
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration

National Marine Fisheries Service

Alaska Fisheries Science Center

December 2010
NOAA Technical Memorandum NMFS
The National Marine Fisheries Service's Alaska Fisheries Science Center
uses the NOAA Technical Memorandum series to issue informal scientific and
technical publications when complete formal review and editorial processing
are not appropriate or feasible. Documents within this series reflect sound
professional work and may be referenced in the formal scientific and technical
literature.
The NMFS-AFSC Technical Memorandum series of the Alaska Fisheries
Science Center continues the NMFS-F/NWC series established in 1970 by the
Northwest Fisheries Center. The NMFS-NWFSC series is currently used by
the Northwest Fisheries Science Center.
This document should be cited as follows:

B. P. Kelly, J. L. Bengtson, P. L. Boveng, M. F. Cameron, S. P. Dahle,
J. K. Jansen, E. A. Logerwell, J. E. Overland, C. L. Sabine, G. T. Waring,
and J. M. Wilder 2010. Status review of the ringed seal (Phoca hispida).
U.S. Dep. Commer., NOAA Tech. Memo. NMFS-AFSC-212, 250 p.
Reference in this document to trade names does not imply endorsement by the
National Marine Fisheries Service, NOAA.
NOAA Technical Memorandum NMFS-AFSC-212
Status Review of the Ringed Seal
(Phoca hispida)
by
B. P. Kelly1, J. L. Bengtson1, P. L. Boveng1, M. F. Cameron1,
S. P. Dahle1, J. K. Jansen1, E. A. Logerwell1, J. E. Overland2,
C. L. Sabine2, G. T. Waring3, and J. M. Wilder4
1 Alaska Fisheries Science Center
7600 Sand Point Way NE
Seattle, WA 98115
www.afsc.noaa.gov
2 Pacific Marine Environmental Laboratory
Office of Oceanic and Atmospheric Research
7600 Sand Point Way NE
Seattle, WA 98115
3 Northeast Fisheries Science Center
166 Water Street
Woods Hole, MA 02543
4 U.S. Fish and Wildlife Service, Alaska Region, Marine Mammals Management
1011 East Tudor Road
Anchorage, AK 99503
U.S. DEPARTMENT OF COMMERCE
Gary F. Locke, Secretary
National Oceanic and Atmospheric Administration
Jane Lubchenco, Under Secretary and Administrator
National Marine Fisheries Service
Eric. C. Schwaab, Assistant Administrator for Fisheries
December 2010
This document is available to the public through:
National Technical Information Service
U.S. Department of Commerce
5285 Port Royal Road
Springfield, VA 22161
www.ntis.gov
STATUS REVIEW OF THE RINGED SEAL 
(Phoca hispida) 
Photo by Brendan P. Kelly 

Prepared and Edited by: 
The 2010 Ringed Seal Biological Review Team 
Brendan P. Kelly1 (Chair), John L. Bengtson1, Peter L. Boveng1, Michael F. Cameron1, 
Shawn P. Dahle1, John K. Jansen1, Elizabeth A. Logerwell1, James E. Overland2, 
Christopher L. Sabine2, Gordon T. Waring3, and James M. Wilder4 
With Contributions by: 
Josh M. London1, Erin E. Moreland1, Tamara L. Olson5, Duane E. Stevenson1, and Muyin Wang6,2 
1 Alaska Fisheries Science Center, National Marine Fisheries Service, 
7600 Sand Point Way NE, Seattle, WA 98115 
2 Pacific Marine Environmental Laboratory, Office of Oceanic and Atmospheric Research, 
7600 Sand Point Way NE, Seattle, WA 98115 
3 Northeast Fisheries Science Center, National Marine Fisheries Service, 
166 Water Street, Woods Hole, MA 02543 
4 U.S. Fish and Wildlife Service, Alaska Region, Marine Mammals Management, 
1011 East Tudor Road, Anchorage, AK 99503 
5 Protected Resources Division, Alaska Region, National Marine Fisheries Service, 
222 West 7th Ave., Anchorage, AK 99513 
6 Joint Institute for the Study of the Atmosphere and Ocean, University of Washington, 
Box 355672, Seattle, WA 98195 
December 2010

CONTENTS 
Contents ...................................................................................................................................................... vii 
Executive Summary ...................................................................................................................................... xi 
1  Introduction .......................................................................................................................................... 1 
2  Species Background .............................................................................................................................. 3 
2.1 Taxonomy and Phylogeny ................................................................................................................... 3 
2.2 Species Description ............................................................................................................................. 4 
2.3 Behavior .............................................................................................................................................. 5 
2.4 Seasonal Distribution, Habitat‐use, and Movements ......................................................................... 8 
2.4.1 Open‐water period..................................................................................................................... 10 
2.4.2 Subnivean period ....................................................................................................................... 12 
2.4.3 Basking period ............................................................................................................................ 14 
2.5 Reproduction and Molting ................................................................................................................ 14 
2.6 Vital Parameters ................................................................................................................................ 16 
2.7 Foraging and Diet .............................................................................................................................. 18 
2.7.1 Marine environment .................................................................................................................. 18 
2.7.2 Freshwater environment ........................................................................................................... 26 
2.8 Historic and Current Abundance and Trends .................................................................................... 26 
2.8.1 Arctic ringed seals ...................................................................................................................... 27 
2.8.1.1 Greenland Sea and Baffin Bay ............................................................................................. 27 
2.8.1.2 Hudson Bay ......................................................................................................................... 28 
2.8.1.3 Beaufort and Chukchi Seas ................................................................................................. 29 
2.8.1.4 White, Barents, Kara, and East Siberian Seas ..................................................................... 30 
2.8.2 Okhotsk ringed seals .................................................................................................................. 30 
2.8.3 Baltic ringed seals ...................................................................................................................... 31 
2.8.4 Ladoga ringed seals .................................................................................................................... 32 
2.8.5 Saimaa ringed seals .................................................................................................................... 32 
3  Species Delineation ............................................................................................................................. 35 
3.1 Evaluation of Discreteness ................................................................................................................ 35 
3.1.1 Separation by Physical, Physiological, Ecological, or Behavioral Factors .................................. 35 
vii
3.1.2 Delimitation by International Differences in Management and Regulatory Mechanisms ........ 38 
3.2 Evaluation of Significance ................................................................................................................. 39 
3.3 Determination of Distinct Population Segments .............................................................................. 39 
4  Extinction Risk Assessment ................................................................................................................. 41 
4.1 Time Frame: The Foreseeable Future ............................................................................................... 41 
4.1.1 Factors in the Foreseeability of Threats to Ringed Seals ........................................................... 41 
4.1.2 Factors in the Foreseeability of Ringed Seal Responses to Threats ........................................... 43 
4.1.3 Lack of a Single Time Frame for the Foreseeable Future ........................................................... 44 
4.2 Analysis of Factors Listed Under Section 4(a)(1) of the Endangered Species Act ............................ 44 
4.2.1 Present or Threatened Destruction, Modification, or Curtailment of the Species’ Habitat or 
Range .................................................................................................................................................. 44 
4.2.1.1 Global climate change ......................................................................................................... 44 
4.2.1.2 Impacts of global climate change on ringed seals ............................................................ 104 
4.2.2 Overutilization for Commercial, Recreational, Scientific, or Educational Purposes ................ 113 
4.2.2.1 Commercial, subsistence, and illegal harvest ................................................................... 113 
4.2.2.2 Scientific and educational utilization ................................................................................ 120 
4.2.3 Diseases, Parasites, and Predation .......................................................................................... 121 
4.2.3.1 Diseases ............................................................................................................................. 121 
4.2.3.2 Parasites ............................................................................................................................ 124 
4.2.3.3 Predation ........................................................................................................................... 126 
4.2.4 Inadequacy of Existing Regulatory Mechanisms ...................................................................... 129 
4.2.4.1 Existing conservation efforts ............................................................................................. 129 
4.2.5 Other Natural or Human Factors Affecting the Species’ Continued Existence ........................ 140 
4.2.5.1 Pollution and contaminants .............................................................................................. 140 
4.2.5.2 Oil and gas exploration, development, and production ................................................... 147 
4.2.5.3 Wind farms ........................................................................................................................ 161 
4.2.5.4 Commercial fisheries interactions and bycatch ................................................................ 161 
4.2.5.5 Shipping and transportation ............................................................................................. 164 
4.2.6 Threats Assessment ................................................................................................................. 174 
4.3 Analysis of Demographic Risks ........................................................................................................ 180 
4.3.1 Abundance ............................................................................................................................... 180 
4.3.2 Productivity .............................................................................................................................. 183 
viii
4.3.3 Spatial Structure ....................................................................................................................... 185 
4.3.4 Diversity ................................................................................................................................... 187 
4.3.5 Relevant Modifying or Mitigating Factors ............................................................................... 189 
4.3.5.1 Life‐history characteristics ................................................................................................ 189 
4.3.5.2 Population characteristics ................................................................................................. 190 
4.3.5.3 Habitat characteristics ...................................................................................................... 190 
4.3.6 Demographic Risks Assessment ............................................................................................... 191 
4.4 Conclusions of the Extinction Risk Assessment .............................................................................. 193 
4.4.1 Arctic ringed seals .................................................................................................................... 193 
4.4.2 Okhotsk ringed seals ................................................................................................................ 193 
4.4.3 Baltic ringed seals .................................................................................................................... 194 
4.4.4 Ladoga ringed seals .................................................................................................................. 194 
4.4.5 Saimaa ringed seals .................................................................................................................. 194 
5  Acknowledgments ............................................................................................................................. 195 
6  Citations ............................................................................................................................................ 197 
7  Appendix: Glossary of Abbreviations ................................................................................................ 249 

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